High Density Boron Carbide Ceramics

Abstract

Porous preforms of B₄C + C and B₄C + C + Si materials were impregnated by liquid (molten) silicon to obtain high-density product with a relative density of 99.0 % and porosity of 0.9%. Silicon impregnation was carried out by saturating the samples through the pores of the SiC + C sacrificial preforms. This method allows to reduce both the dissolution of boron carbide grains in the silicon solution and the formation of the B₁₂(C, Si, B)₃ phase. This reduces the fragility of the product and thereby improves the mechanical characteristics of the B₄C ceramics.